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In this paper, a new type of copper (Cu) matrix graphite composite was successfully prepared, which was reinforced with titanium nitride particles (TNPs) using powder metallurgy. These composites contained 2 wt % graphite as the lubricating phase and 1, 3, 5, 10, and 15 wt % TNPs as the reinforcing phase. The effects of different TNP contents on composite properties and the composites' wear mechanism were examined. The samples were characterized by microstructure, density, porosity, hardness, compressive yield strength, and friction wear testing. The results showed that, with TNP addition, the hardness, compressive strength, and friction and wear properties of the composites were improved. When the TNP content was >3 wt %, composite porosity gradually increased and the hardness, compressive strength, and friction and wear properties of the composites sharply decreased. With TNP addition, the main composite wear modes gradually changed from adhesive and abrasive wear to abrasive wear.

Graphite particles and boron carbide (B4C) particles were added into copper matrix composites by powder metallurgy to form a new composite-reinforced and lubricated system. The effects of different amounts of B4C particles on the properties of composites were studied. With addition of 2 wt % graphite powder as the solid lubricating phase, the effects of B4C particle content on the microstructure, density, porosity, Vickers hardness, compressive strength, and the friction and wear properties of the copper-matrix/graphite self-lubricating composite materials were investigated. The results indicate that increasing addition of B4C particles significantly improved the density, Vickers hardness, compression strength; friction and wear properties of composites. However, excess B4C particles also increased porosity. The connected netted B4C particles disrupt the continuity of the metal matrix causing serious decreases in density, Vickers hardness, compression, and the friction and wear properties of the composite material. Of the tested composites, the materials containing 1.5 wt % B4C showed the best friction and wear resistance properties.

In this study, a set of red, green and blue LEDs (RGB LEDs) with a pulse width modulation (PWM) driver circuit are used to fabricate a 5700 K lamp that is used to optimize the light harvesting capability and energy output of dye-sensitized solar cells (DSCCs). By separately controlling the duty cycles of the driving signals of the RGB LEDs, it is demonstrated that the energy harvesting efficiency is elevated by 71.72%. Compared to RGB LEDs driven by direct current, using the RGB LEDs driven by PWM signals helps increase the light energy harvesting efficiency by 137.97%, while LED power consumption is also reduced by 52.38%.

We design a novel phase real-time microscope camera (PhaseRMiC) for live cell phase imaging. PhaseRMiC has a simple and cost-effective configuration only consisting of a beam splitter and a board-level camera with two CMOS imaging chips. Moreover, integrated with 3-D printed structures, PhaseRMiC has a compact size of 136×91×60 mm3, comparable to many commercial microscope cameras, and can be directly connected to the microscope side port. Additionally, PhaseRMiC can be well adopted in real-time phase imaging proved with satisfied accuracy, good stability and large field of view. Considering its compact and cost-effective device design as well as real-time phase imaging capability, PhaseRMiC is a preferred solution for live cell imaging.

The ciprofloxacin (CIP) abuse has caused many problems threatening to human health. Here, we design the quantum dot microsphere (QDM) based immunochromatographic quantitative CIP test strip: when the sample under detection contains CIP, the QDM-monoclonal antibody (mAb) probes bound with the CIP and cannot be captured by CIP-bovine serum albumin (BSA) conjugation dispersed on the T lines, reducing the fluorescence intensities. These test strips can provide a low detection limit of 0.05 ng/mL and a wide linear detection range from 0.1 ng/mL to 100 ng/mL in high sensitivity and accuracy as well as good selectivity, reproducibility and stability. Moreover, a smartphone based test strip reader with the size of 85 mm × 48 mm × 44 mm is also fabricated using 3-D printing to automatically and quantitatively detect CIP. The whole process of CIP detection can be finished within 15 min, but only cost ~1 RMB (10 cents).

The x(Ca0.8Na0.1Sm0.1)TiO3–(1 − x)(Sm0.5Nd0.5)AlO3 (CNST–SNA, 0.60 ≤ x ≤ 0.75) ceramic materials were prepared by a conventional two-step solid-state reaction route. The effects of the sintering temperature and composition on the phases, microstructures, and microwave dielectric properties were investigated. The optimal sintering temperature of the CNST–SNA ceramics was found at 1475 °C. The optimal microwave dielectric properties were achieved at x = 0.69 with er = 43.8, Q × f = 34303 GHz (at 5.968 GHz), and τf = − 1.64 ppm/°C.

The microstructure evolution of semi-solid SiCp/AZ91D nanocomposite during isothermal heat treatment process in the mushy-zone was investigated. The results indicate that the nano-size SiC particles in composite are distributed uniformly and the grains are refined significantly by the addition of nano-size SiC particles. The semi-solid microstructure evolution experiences four stages during isothermal heat treatment process: the initial coarsening, structural separation, spheroidization and final coarsening. The grain size of the primary α-Mg phase decreases with the increasing of holding temperature. With the prolongation of holding time, the grain size of the primary α-Mg phase decreases at first and then increases. The optimum isothermal heat treatment parameter is 575℃ for 30min, under which the average grain diameter is 58μm and shape factor is 1.25.

The effects of Mg content, inclusion size, and austenite grain size on the intragranular acicular ferrite (IAF) nucleation in heat-affected zone of steel plate after high-heat-input welding of 400 kJ/cm were investigated by welding simulation and observation using a scanning electron microscope equipped with an energy dispersive spectrometer and an optical microscope. The IAFs are observed in steel with Mg addition, and the volume fraction of IAF is as high as 55.4% in the steel containing 0.0027 mass% Mg. The MgO–Al2O3–Ti2O3–MnS inclusions with size around 2 μm are effective nucleation sites for IAF, whereas Al2O3–MnS inclusions are impotent to nucleate the acicular ferrite. The prior-austenite grain (PAG) size distribution in low Mg steel is similar to that in steel without Mg addition. The austenite grain with size about 200 μm is favorable for the IAF formation. In the steel with high Mg content of 0.0099%, the growth of PAG is greatly inhibited, and PAG sizes are smaller than 100 μm. Therefore, the nucleation of IAF can hardly be observed.

In order to increase the energy harvesting capability of dye-sensitized solar cells (DSSCs), a white light LED with a pulse width modulation (PWM) driver circuit is proposed as the light source for DSSC power generation. With the frequency and duty of driving signals acting as the adjustable parameters, it is demonstrated that the efficiency of DSSCs can be elevated by 8%. White LEDs driven by direct current are the mainstay of the current LED lighting market, but if the PWM LEDs are used instead, our experimental results show that the DSSC efficiency can be increased 4.52%, with an overall 4.31% savings in LED power consumption.

A lead-chelating ligand, 2,2′-((1E)-((4-((2-mercaptoethyl)thio)-1,2phenylene)bis(azany-lylidene))bis(methanylylide-ne))diphenol (ETBD), was immobilized on a nanocomposite Fe3O4@Au/MoS2/GN possessing a large surface area to produce a biomimetic sensor. The ETBD molecules act as specific receptor binding sites for Pb2+, resulting in the highly selective Pb2+ response by square wave voltammetry (SWV). In order to obtain highly sensitive analysis, MoS2/GN was utilized as a substrate material, which enhances sensing performance and provides sites for Fe3O4@Au, and the core–shell Fe3O4@Au can interconnect and produce conductivity between the recognition element and nanomaterials. Due to the integration of the properties of Fe3O4@Au, MoS2/GN and ETBD, the proposed biomimetic electrochemical sensor exhibits a wide linear response range from 4 × 10−14 to 2 × 10−8 mol/L with a low detection limit of 3.38 × 10−14 mol/L, which shows great promise for the determination of ultra-trace Pb2+ in real samples.

Transition metal dichalcogenide (TMD) materials have received enormous attention due to their extraordinary optical and electrical properties, with ${\mathrm{MoS}}_{2}$ being one of the most representative examples. As the thickness increases from monolayer to multilayer, the photoluminescence (PL) of ${\mathrm{MoS}}_{2}$ is gradually quenched due to the direct-to-indirect band gap transition. How to enhance PL response and decrease the layer dependence in multilayer ${\mathrm{MoS}}_{2}$ remains a challenge. In this work, we report simultaneous generation of three PL peaks at around 1.3, 1.4, and 1.8 eV on multilayer ${\mathrm{MoS}}_{2}$ bubbles. The temperature dependent PL measurements indicate that the two peaks at 1.3 and 1.4 eV come from phonon-assisted indirect-gap transitions while the peak at 1.8 eV comes from the direct-gap transition. The weakening of interlayer coupling on multilayer ${\mathrm{MoS}}_{2}$ bubbles, which may account for the emergence of PL peaks, is confirmed by the low-frequency Raman spectroscopy. Using first-principles calculations, the band structure evolution of multilayer ${\mathrm{MoS}}_{2}$ under strain is studied, from which the origin of the three PL peaks of ${\mathrm{MoS}}_{2}$ bubbles is further confirmed. Moreover, PL standing waves are observed in ${\mathrm{MoS}}_{2}$ bubbles that create Newton-Ring-like patterns. This work demonstrates that the bubble structure may provide new opportunities for engineering the electronic structure and optical properties of layered materials.

The effect of Mg content on the microstructure and toughness of the heat-affected zone (HAZ) of steel plates after high heat input welding was investigated by means of welding thermal simulation test and in situ observation through high-temperature laser scanning confocal microscopy. It was found that with the increase of Mg content in the steel, the former austenite grain sizes were greatly decreased and the mainly microstructural constituents in HAZ were changed from the brittle constituents of Widmanstatten ferrite, ferrite side plate and upper bainite to the ductile constituents of intragranular acicular ferrite and polygonal ferrite. The proportion of grain boundary ferrite was decreased greatly with the further addition of Mg from 27 to 99 ppm. As a result, the HAZ toughness after welding with heat input of 400 kJ cm−1 is increased with increasing Mg content in the steel plate.

The characteristics of inclusions in Fe-16Mn-xAl-0.6C (x = 0.002, 0.033, 0.54, 2.10 mass pct) steels have been investigated and their effects on hot ductility of the high manganese TWIP steels have been discussed. Ductility is very poor in the steel containing 0.54 mass pct aluminum, which is lower than 20 pct in the temperature range of 873 K to 1473 K (600 °C to 1200 °C). For the steels containing 0.002 and 2.10 mass pct aluminum, ductility is higher than 40 pct in the same temperature range. The hot ductility of steel containing 0.033 mass pct aluminum is higher than 30 pct throughout the temperature range under examination. With increasing aluminum content, the main inclusions in the steels change along the route of MnO/(MnO + MnS) → MnS/(Al2O3 + MnS) → AlN/(Al2O3 + MnS)/(MgAl2O4 + MnS) → AlN. The thermodynamic results of inclusion types calculated with FactSage software are in agreement with the experimental observation results. The inclusions in the steels containing 0.002 mass pct aluminum do not deteriorate the hot ductility. MnS inclusions whose average size, number density, and volume ratio are 1.12 μm, 15.62 mm−2, and 2.51 × 10−6 in the steel containing 0.033 mass pct aluminum reduce the ductility. In the steel containing 0.54 mass pct aluminum, AlN inclusions whose average size, number density, and volume ratio are 0.878 μm, 16.28 mm−2 and 2.82 × 10−6 can precipitate at the austenite grain boundaries, prevent dynamic recrystallization and deteriorate the hot ductility. On the contrary, in the steel containing 2.10 mass pct aluminum, the average size, number density and volume ratio of AlN inclusions change to 2.418 μm, 35.95 mm−2, and 2.55 × 10−5. They precipitate in the matrix, which do not inhibit dynamic recrystallization and thereby do not lead to poor hot ductility.

Many proteins exist in natures as oligomers with various quaternary structural attributes rather than as single chains. Predicting these attributes is an essential task in computational biology for the advancement of proteomics. However, the existing methods do not consider the integration of heterogeneous coding and the accuracy of subunit categories with limited data. To this end, we proposed a tool that can predict more than 12 subunit protein oligomers, QUATgo. Meanwhile, three kinds of sequence coding were used, including dipeptide composition, which was used for the first time to predict protein quaternary structural attributes, and protein half-life characteristics, and we modified the coding method of the functional domain composition proposed by predecessors to solve the problem of large feature vectors. QUATgo solves the problem of insufficient data for a single subunit using a two-stage architecture and uses 10-fold cross-validation to test the predictive accuracy of the classifier. QUATgo has 49.0% cross-validation accuracy and 31.1% independent test accuracy. In the case study, the accuracy of QUATgo can reach 61.5% for predicting the quaternary structure of influenza virus hemagglutinin proteins. Finally, QUATgo is freely accessible to the public as a web server via the site http://predictor.nchu.edu.tw/QUATgo.

In the present study, the effect of cooling conditions on the evolution of non-metallic inclusions in high manganese TWIP steels was investigated based on experiments and thermodynamic calculations. In addition, the formation and growth behavior of AlN inclusions during solidification under different cooling conditions were analyzed with the help of thermodynamics and dynamics. The inclusions formed in the high manganese TWIP steels are classified into nine types: (1) AlN; (2) MgO; (3) CaS; (4) MgAl2O4; (5) AlN + MgO; (6) MgO + MgS; (7) MgO + MgS + CaS; (8) MgO + CaS; (9) MgAl2O4 + MgS. With the increase in the cooling rate, the volume fraction and area ratio of inclusions are almost constant; the size of inclusions decreases and the number density of inclusions increases in the steels. The thermodynamic results of inclusion types calculated with FactSage are consistent with the observed results. With increasing cooling rate, the diameter of AlN decreases. When the cooling rate increases from 0.75 to 4.83 K s−1, the measured average diameter of AlN decreases from 4.49 to 2.42 μm. Under the high cooling rate of 4.83 K s−1, the calculated diameter of AlN reaches 3.59 μm at the end of solidification. However, the calculated diameter of AlN increases to approximately 5.93 μm at the end of solidification under the low cooling rate of 0.75 K s−1. The calculated diameter of AlN decreases with increasing cooling rate. The theoretical calculation results of the change in diameter of AlN under the different cooling rates have the same trend with the observed results. The existences of inclusions in the steels, especially AlN which average sizes are 2.42 and 4.49 μm, respectively, are not considered to have obvious influences on the hot ductility.

The solidification structures and the thermal properties of Fe-Mn-C steel ingots containing different manganese contents have been investigated and the phase transformation characteristics have been revealed by Thermo-Calc to assist development of the continuous casting technology of Fe-Mn-C steels. The results show that the thermal conductivity of the 0Mn steel is higher than that of the 3Mn steel. The thermal conductivity of the 6Mn steel is the lowest in the three kinds of steels below 1023 K (750 °C) and the highest above 1173 K (900 °C). The 0Mn steel has the highest value of the proportion of equiaxed grain zone area in the three kinds of steels, whereas the 3Mn steel has the lowest value of it in the steels. Manganese has the effect of promoting the coarsening of grains. The microstructure is martensite and a little retained austenite (3.8 mass pct) in the 6Mn steel, whereas the microstructure is bainite in the 3Mn steel. The 0Mn steel is characterized by ferrite and pearlite. The mean thermal expansion coefficients of the steels are in the range from 1.0 × 10−5 to 1.6 × 10−5 K−1, and the determinations of mold tapers of the 6Mn and 3Mn steels can refer to low-carbon steel. Using RA

Laser deposition was adopted to prepare novel Ni-based solid solution (γ-NiCrAlTi)/ TiC/α-Ti/CaF2 high-temperature self-lubricating wear resistant composite coating on Ti6Al4V alloy. Microstructure, micro-hardness, wear behavior, and counter-body effect of the coating were investigated systematically. It can be seen that the coating mainly consists of γ-NiCrAlTi, TiC, α-Ti, and small fine CaF2 particles. Average micro-hardness of the coating is 1023 HV0.3, which is about three-factor higher than that of Ti6Al4V substrate (380 HV0.3). The friction coefficient and wear rate of the coating decrease at all test temperatures to different extents with respect to the substrate. The improvement in wear resistance is believed to be the combined effects of the γ-NiCrAlTi solid solution, the dominating anti-wear capabilities of the reinforced TiC carbides, and the self-lubricating property of CaF2.

A miniaturized microstrip low-pass filter (LPF) with ultra-wide stopband is proposed, where improved Koch fractal curve defected ground structure (DGS) resonators are implemented in its design. The improved Koch fractal DGS is composed of a specific schematic Π-shaped DGS with improved Koch fractal curve at both terminations. By using this structure, the filter not only supports conventional DGS performances such as a sharp transition to the stop band, but also exhibits an ultrawide stopband compared with traditional dumbbell-shaped DGS (DB-DGS) filters. The filter containing 2 unit cells has a compact size of 36.8×24 mm2 and operates with an insertion loss of less than 1 dB from dc to 2 GHz. From 2.2 GHz to 6.3 GHz, the rejection is better than 40 dB. The proposed asymmetric Koch fractal DGS-LPF is easily integrated into RF/microwave circuitry at a low manufacturing cost, especially for wireless communication.

In the present paper, the nano-indentation technique is used to investigate the effects of inclusions on machinability of free-cutting steel. Firstly, the hardness, elastic moduli, and load–displacement curves of inclusions are analyzed and compared with matrix. Secondly, the effects of inclusions on machinability are investigated using nano-indentation measurements and thermodynamic calculations. Lastly, errors of nano-indentation measurements and macrohardness tests are analyzed. The hardness of BN is lower than that of MnS. Both of them have lower hardness than those of matrices. Since the hardness of Al2O3 and TiN is higher than that of matrices, they exist as hard spots in steels. The elasticities of BN and MnS are much better than those of Al2O3, TiN, and matrices. BN and MnS which have lower hardness values and better elasticities than matrices can improve the machinability of steel effectively. Special attention should be paid to the effects of inclusions in steel on the results of nano-indentation measurement and macrohardness test.

The effects of the cooling rate on the morphology and diameter distribution of BN inclusions and the solidification structure have been observed. The precipitation and growth behavior of BN inclusions during solidification have been analyzed with the help of thermodynamics and kinetics. The experimental results show that the diameter of BN inclusions increases with the decrease of cooling rate. The calculation results show that the segregation of boron is much stronger than that of nitrogen. Considering the segregation of solutes, BN formation takes place only in the mushy region when the solid fraction is close to 1 during solidification of BN free-machining steel. The difference between the nitrogen concentration in the remnant liquid phase increased by segregation and that in equilibrium is a driving force for BN growth. With the increase of cooling rate, the time for BN growth decreases and the radius of the precipitated BN inclusions is reduced.

The modified resins, as antibacterial coating materials, have attracted wide attention. Two steps to obtain resins: cuprous oxide collosol particle was prepared by reduction of Copper acetate solution, using hydrazine as the reducing agent, then oleic acid was added to the system as the covered agent; silicone and cuprous modified acrylic resin was successfully synthesized by solution polymerization with the monomers of acrylic acid (AA), butyl acrylate (BA), methyl methacrylate (MMA), vinyl triethoxy silane (VTES) and the as-prepared oleic acid coated Cu2O sol, using the azobisisobutyronitrile (AIBN) as the initiator. The samples were characterized by X-ray Photoelectron Spectroscopy (XPS) and FTIR analysis. The effects of silicone content on the properties of polymer coatings were investigated by contact angle analysis.

A new self-compensation method is proposed in this paper. The impedance of a quartz tuning fork changes along with the temperature. A digital driving circuit is designed so that the frequency can be adjusted by controlling the phase. The relationship between the driving amplitude and the temperature is captured in a digital circuit, which can reflect the temperature information. As the relationship is nonlinear, after third-order fitting, the temperature has a precision of 2.356 °C. Finally, the bias stability is optimized and the drift decreases to 1.7 %.

In milling process, cutting force is the main cause of machining deformation, and in machining of thin-walled parts, machining deformation is the major factor for machining error. In this paper, through finite element analysis software ABAQUS, three-dimensional simulation analysis on the machining of SiCp/Al composite thin-walled parts with a polycrystalline diamond tool have been carried out. It reveals the influence of radial depth of cut, cutting speed, and feed per tooth on cutting force. Analysis results show that: higher speed, small radial depth of cut and moderate feed per tooth can effectively reduce cutting force and inhibit deformation. In addition, a comparison is made between analysis results of milling force and high accuracy milling force prediction model, results from the two methods are similar.

The precipitation and control of boron nitrogen (BN) inclusions in 42CrMo steel were investigated and their effect on machinability was analyzed. First, the precipitation regularity of BN in 42CrMo steel was studied by theoretical calculation. Then, the machinability of the steel was investigated through contrast cutting experiments, and the composition and cooling rate of the steel were controlled to analyze the variation laws of the size, distribution, and area ratio of BN inclusions. Finally, the results were combined with the machinability of the steel to analyze the relationship among them. It is found that the machinability of the steel is mainly influenced by the diameter and quantity of BN inclusions. Fine and dispersedly distributed BN inclusions are more beneficial for the improvement in machinability of 42CrMo steel than coarse and sparse BN inclusions.

Catalytic gasification of sawdust biomass was carried out using a specially designed flow-type double beds micro reactor in a two step process: temperature programmed non-catalytic air gasification of biomass was performed in the first bed at 800°C followed by catalytic decomposition gasification of volatile matters (including tars) in the second bed at five different temperatures. The general observation is that the conversion of sawdust biomass increases as the temperature was raised from 750 to 950°C over non-catalyst, raw copper slag or calcined copper slag. High temperature enhances secondary cracking and reforming of tars and heavy hydrocarbons. At the temperature of 950°C, the energy yield (Ey) was 13.2 MJ gas/kg biomass; The energy conversion efficiency (Eff) was 81.05%; The H2production was 0.0296 kg/kg biomass; The CO production was 0.6685 kg/kg biomass. Furthermore, improvement in conversion of biomass is observed when copper slag is added in secondary reactor as catalysts. The use of copper slag as catalysts significantly contributes to tar conversion in lighter hydrocarbons.

The influencing factors on precipitation and the suitable controlling conditions of BN inclusions were not reported until now, although it has been proven that BN could improve the cutting performance of steel. The precipitation and control of BN inclusions have been investigated in detail in this article. First, the precipitation behaviors of main inclusions in steel have been investigated by theoretical calculation, especially those of BN inclusions. Then, the directional solidification and heat treatments were applied to study the precipitation of BN inclusions realistically, and the microstructures of steels under different cooling rates have been analyzed. The variation laws of size, distribution, and area ratio of BN inclusions were discussed under conditions of quantitative control of chemical composition and cooling rate of steel. The variation laws and the main influencing factors of precipitation of BN inclusions in steel have been obtained and the suitable controlling conditions have been proposed. Finally, it is validated with a cutting experiment that the cutting performance and the chip-breaking performance of steel have been greatly improved by BN inclusions precipitated in the suitable control conditions.

In this study, a light-driving bug zapper is presented for well controlling the diseases brought by insects, such as mosquitoes. In order to have the device efficient to trap the insect pests in off-grid areas, pulse width modulated light emitting diodes (PWM-LED) combined with a solar power module are proposed and implemented. With specific PWM electric signals to drive the LED, it is found that no matter what the ability of catching insects or the consumed power efficiency can be enhanced thus. It is demonstrated that 40% of the UV LED consumed power and 25.9% of the total load power consumption can be saved, and the trapped mosquitoes are about 250% increased when the PWM method is applied in the bug zapper experiments.

Automobile crankshaft steel 42CrMo, which requires excellent machinability and mechanical properties, cannot be manufactured by traditional methods. To achieve these qualities, the formation behavior of boron nitride (BN) inclusions in 42CrMo steel was studied in this article. First, the precipitation temperature and the amount of BN type inclusions with different contents of boron and nitrogen in molten steel were calculated thermodynamically by FactSage software. Then the morphology and the size of BN type inclusions as well as the influence of cooling methods on them were investigated by scanning electron microscopy. Furthermore, the effects of cooling rate and the contents of B and N in molten steel on the morphology, size, and distribution of BN type inclusions were studied quantitatively and detailedly by directional solidification experiments. It is found that different BN inclusions in molten steel can form by controlling the cooling rate and the contents of B and N, which is important for obtaining the excellent machinability of 42CrMo steel.

This paper proposes a selection and extraction strategy to acquire high quality sperms from a biomimetic microfluidic device capable of generating a dual gradient flow field for motile sperm sorting. The sorter consists of a straight flow zone, a rapidly expansion sector for sperm sorting by gradient up-stream flow, and a dumbbell channel for dead sperms separation at the outlet. A collateral runner is set at the front area of the expansion sector, but mostly kept in dry state without affecting the sorting process. At the end of sorting, a pressure was applied from both the inlet and outlet to flush the high quality sperms into the collateral runner for collection. Controllable numbers, ranging from 1 to 15000, of sperms can be collected with a motility (>60µm) ratio higher than 60%, suitable for in-vitro fertilization (IVF).

Polybenzimidazole (PBI) has been chemically bonded to silica nanoparticles (SNPs) through an ozone-mediated process using N-(p-carboxyphenyl)maleimide (pCPM) functionalized SNPs (SNP-pCPM) as precursors, to enhance the interfacial compatibility between SNPs and PBI in PBI/SNP nanocomposites. The PBI-functionalized SNPs (SNP-PBI) have been well characterized and used as inorganic nanofillers for preparation of PBI/SNP-PBI membranes for fuel cells. Addition of PBI-SNP to PBI membranes enhances their thermal and mechanical properties as well as decreases their phosphoric acid uptakes. For the PBI/SNP-PBI membrane with 10 wt% of SNP-PBI, it shows a proton conductivity of about 50 mS cm−1 at 160 °C, which is 25% higher compared to the pristine PBI membrane. Consequently, the PBI/SNP-PBI membrane demonstrates a maximum power density of 650 mW cm−2 in a single cell test, compared to the value of 530 mW cm−2 read from the test for pristine PBI membrane.

In this paper, the mineralogical characteristics of Brazil kaolinite and Beihai kaolinite have been researched. The structure and performance of samples were systematically analyzed by X-ray diffraction (XRD), scanning electronic microscopy (SEM) and transmission electron microscopy (TEM).The results showed that Brazil kaolinite had inerratic pseudo-hexagonal morphology, low diameter-thickness ratio and a Hinckey index of 1.501. While Beihai kaolinite has irregular-polygonous morphology, higher diameter -thickness ratio and a Hinckey index of 1.197. The differences in structural make them have different physical properties.

A novel design of optical sampling system has been developed by using sum-frequency generation (SFG) in a periodically-poled lithium niobate (PPLN) waveguide and using passive mode-locked fiber laser pulses as optical sampling pulses. The system achieved high temporal resolution and high sensitivity using a 30 mm length PPLN with quasi phase match period of 19.3 μm and 151 fs sampling pulses which were generated by passive modelock fiber laser based on nonlinear polarization rotation (NPR). Clear eye-diagram of 10 Gbit/s non-return-to-zeros (NRZ) pseudorandom binary sequence (PRBS) optical signal were successfully reconstructed by this system.

By using amines with different lengths, two layered cobalt-molybdenum phosphates with different interlayer distances, (C{sub 2}N{sub 2}H{sub 10}) [HCo(H{sub 2}O){sub 2}P{sub 2}MoO{sub 10}] (1), and (C{sub 3}N{sub 2}H{sub 12}){sub 4{l_brace}}Co{sub 3} [P{sub 4}Mo{sub 6}O{sub 26}(OH){sub 5}]{sub 2{r_brace}}. 5H{sub 2}O (2), have been hydrothermally synthesized and characterized. In compound 1, the H{sub 2}en direct the [CoMoP{sub 2}] clusters to form a layered framework. By changing the lengths of protonated organic amines (H{sub 2}en to 1, 3-H{sub 2}pn), compound 2 is obtained, in which the sandwich-shaped [Co (Mo{sub 6}P{sub 4}){sub 2}] clusters are linked by tetrahedrally coordinated cobalt into a layered framework. With the lengths of protonated organic amines increasing, the interlayer distances in compound 2 become larger. This work successfully demonstrates that tuning the lengths and conformation of the protonated organic amines can provide a facile route for the formation of organically templated inorganic open-framework materials. Additionally, susceptibility measurement shows that the two compounds both exhibit antiferromagnetic interactions. -- Graphical abstract: By using amines with different lengths, two layered cobalt-molybdenum phosphates with different interlayer distances have been hydrothermally synthesized. Display Omitted Research highlights: {yields} Two layered compounds have been synthesized by utilizing amines with different lengths. {yields} The chain lengths ofmore » amines can influence the overall supramolecular framework of the PMo-TMCs. {yields} The conformation of amines may influence the stacking mode of the inorganic building blocks. {yields} Susceptibility measurement shows that the two compounds both exhibit antiferromagnetic interactions.« less

Conversion wavelength and power dependence of the time delay and output signal quality for an optical delay system consisting of dispersion compensation fiber (DCF) and highly nonlinear fibers (HNLFs) is investigated in this paper. The numerical results show that the time delay generally varies linearly with the conversion wavelength propagating through DCF and changes slightly with the power launched into HNLFs. But it has abrupt change at some values of conversion wavelength or input power level. Output signal quality of the overall system varies significantly with the conversion wavelength and input power level. The reasons behind these results are analyzed. Finally, the input power level is optimized to achieve linearly varying time delay and desirable output signal quality for an optical delay system.

We investigated the effect of subgrain boundaries on periodic domain-inverted structures with a period of 30 lm in near-stoichiometric LiTaO3 (SLT) crystals and found that they negligibly affected the structures. Using SLT crystals having subgrain boundaries and a quasi-phase matching technique, we fabricated a 2-mm-thick, 60-mm-long periodically poled SLT frequency converter with a domain-inverted structure with a 30.5-lm period and demonstrated optical parametric oscillation. 2008 Elsevier B.V. All rights reserved.

This study proposes the addition of SiO2 scattering-particles into the phosphor layer of a multi-chip white light LED (MCW-LED) for enhancing its performances. It is demonstrated by computer simulations that SiO2 particles can bring significant effects on the correlated color temperature (CCT) uniformity and luminous flux. Through the simulation experiments, it is found that the MCW-LED with hybrid SiO2 structure with SiO2 particle size around 1 µm can achieve higher color uniformity than other package structures. We investigate the influence of SiO2 (quartz) concentration on the CCT and the output flux of the MCW-LED with CCTs 7000, 7700 and 8500 K, respectively. Comparing with the LED package without SiO2, SiO2 packages can shrink the CCT deviation about 48 %. In the study, it is demonstrated that the participation of about 5–10 % SiO2 can accomplish the MCW-LED with higher spatial color uniformity and optimal lumen output.

A wide angle light-deflected lens combining collimation and total internal reflection (TIR) optical mechanics for LED package is proposed. Utilizing angle-dividing method the angle of emitting distribution of LED chip was cut into several angular zones and then a light-collimating curve surface with corresponding declined plane performing TIR for the collimated incident ray was designed. Thereby, the light-deflected lens, consisting of multi pairs of collimating curve surfaces and declined planes, can achieve wide-angle deflection of light emitting from LED chip. The design rule and experiment results of the lens with optimization optical design are demonstrated and discussed in this paper.

The characteristics and the structure of TeO2 acoustic-optic tunable filter used in communication are discussed briefly based on the acoustic-optic theory and it is shown that a large optical incident angle and a long interaction length are suitable for the optical add/drop multiplexer based on the TeO2 acoustic-optic tunable filter. The distribution of acoustic energy flow in the device supports the large optical incident angle. The long interaction length depends on the change of the device structure to some degree. The measured results of the samples show that the diffraction efficiency reaches at 96% in the tuning range larger than 100 nm and the bandwidth is about 2 nm. It can be found that there is a good consistency with the basic theoretical mode. The optimized design result shows that the diffraction efficiency can arrive at 100%, and the bandwidth can be less than 0.4 nm. Thus, the non-collinear TeO2 acoustic-optic tunable filter can play an important role in the coming general optical network.

We investigate the magic wavelengths of the trapping laser for 6S1/2 – 6P3/2 of the Cs atom in a region where the optical shift between two different states can be eliminated. For fine levels and linear polarized laser they are 930.4 nm and 937.2 nm. The magic wavelengths range from 927.7 nm to 945.0 nm for circle-polarized perturbing laser. Effects of nuclear spin, the hyper-fine Zeeman levels, and the polarization of the light, which generate different magic wavelengths, are further discussed.

The molecular structures and physical properties of several single‐ and double‐fluorinated isothiocyanatotolane, isothiocyanatocyclohexyltolane, and isothiocyanatoterphenyl compounds are reported. Two eutectic mixtures comprising these compounds are formulated and their properties evaluated. These mixtures exhibit a high birefringence, relatively low viscosity, high resistivity, and good photo and thermal stabilities. Potential applications of these mixtures for spatial light modulators, optical phased arrays, and high speed photonics are discussed.

nanocopper oxides (Cu2O) materials, which received much attention in recent years, have many promising applications in various areas. The nanocopper oxides were prepared by the reduction of aqueous cupric acetate, with hydrazine as a reductant. The nanocopper oxides Collosol would be very stability when coated by Oleic acid, the oleic acid coats Cu2O nanoparticle through chemical reaction between carboxyl at one end of oleic acid molecule. All the samples were characterized by XRD, SEM and FTIR analysis.

A new organic–inorganic hybrid material, formulated as K[{Cu(imi)(phen)}2Cl][Mo8O26] (1) (imi = imidazole, phen = 1,10-phenanthroline), has been synthesized under hydrothermal conditions and structurally characterized by elemental analysis, IR spectra, thermal analysis and single-crystal X-ray diffraction. Compound 1 consisted of β - [ Mo 8 O 26 ] 4 - cluster, dinuclear copper complex [ Cu ( imi ) ( phen ) 2 Cl ] 3 + and K+ ion, in which the β-octaolybdate building block is linked by the coordination bridge [ Cu ( imi ) ( phen ) 2 Cl ] 3 + and the inorganic bridge K+ into a 2D organic-inorganic framework through M–O–M′ bonds (M = Mo, M′ = Cu, K). The electrochemical behavior of compound 1 has been studied in detail based on a solid bulk-modified carbon paste electrode of compound 1 (1-CPE).

With the development of ultrahigh speed optical communications, optical sampling oscilloscope is a promising candidate for the optical performance monitoring. In this paper, a periodically poled lithium niobate based optical sampling oscilloscope is demonstrated. In the optical sampling oscilloscope, the bit rate adaptive method and chirp Z transform synchronization method are adopted to realize bit rate transparency. The optical sampling is completed by the sum frequency generation effect in periodically poled lithium niobate waveguide. The sampled signal is processed by FPGA based digital signal processing hardware, the eye diagram and parameters such as Q factor are measured. Intensity modulated optical signals with symbol rate from 1.0~25Gbaud are measured with our optical sampling oscilloscope. The experimental results are compared with that measured with Agilent 86100A wide bandwidth optical to electronic (O/E) oscilloscope and EXFO PSO-100 optical sampling oscilloscope. The measurement results of our oscilloscope are much closer to Agilent 86100A oscilloscope. Besides, our optical sampling oscilloscope has the advantage of faster measurement speed and higher synchronization accuracy due to the novel methods we proposed. The operation stability is also measured for our optical sampling oscilloscope, and the steady state can be maintained for several hours.

Illuminance distribution of LED spherical arrays is studied by theoretical analysis and simulation. The optimal layout of the LED spherical array is founded by changing the angle, the ball radius, and the power of different LED. The uniformity of illumination of the LED spherical array is verified, which is better than LED planar array. In addition, the illuminance distribution of indoor ground surface illuminated by LED spherical array with different parameters and the related curves are obtained. The LED spherical array mentioned in this paper can be useful in the application of indoor visible light communication.